https://ntp.niehs.nih.gov/go/9480

Target Organs and Levels of Evidence for TR-372

Toxicology and Carcinogenesis Studies of 3,3'-Dimethoxybenzidine Dihydrochloride (CASRN 20325-40-0) in F344/N Rats (Drinking Water Studies)

Chemical (Study Title)
CASRN		 Peer Review Date Route/Exposure Levels Study Laboratory
3,3'-Dimethoxybenzidine dihydrochloride
20325-40-0		 06/27/1989 Dosed-Water
R: 0,80,170,330 PPM /70,45,75,70 PER GROUP RESPECTIVELY		 Hazleton, Vienna

Levels of Evidence

Male Rats: Clear Evidence
Type Organ/Tissue (Lesion)
Neoplastic Lesions
  • Skin: BASAL CELL OR SEBACEOUS GLAND NEOPLASMS 2/60 33/45 56/75 41/60; SQUAMOUS CELL NEOPLASMS 0/60 13/45 28/75 22/60
  • Liver: NEOPLASTIC NODULE 0/60 3/45 7/74 6/60; NEOPLASTIC NODULE OR CARCINOMA 1/60 1/45 0/74 2/60 COMBINED 1/60 4/45 7/74 8/60
  • Large Intestines: ADENOMATOUS POLYP 0/60 1/45 4/75 5/60 OR ADENOCARCINOMA 0/60 4/45 11/75 8/60 COMBINED 0/60 4/45 14/75 13/60
  • Oral Cavity: SQUAMOUS CELL PAPILLOMA 1/60 7/45 10/75 9/60; SQUAMOUS CELL PAPILLOMA OR SQUAMOUS CELL CARCINOMA 0/60 1/45 0/75 2/60 COMBINED 1/60 8/45 10/75 11/60
  • Zymbal Gland: ADENOMA 0/59 4/45 11/75 9/60; CARCINOMA 0/59 7/45 14/75 21/60
  • Preputial Gland: ADENOMA 14/60 6/43 19/73 12/59 OR CARCINOMA 2/60 6/43 15/73 19/59 COMBINED 16/60 12/43 33/73 29/59
  • Mesothelium (Abdominal Cavity/Tunica Vaginalis): MESOTHELIOMA 2/60 1/45 7/75 6/60
May Have Been Related
  • Brain: ASTROCYTOMA 0/60 2/44 3/75 1/60
Non-Neoplastic Lesions
  • SPLEEN: HEMATOPOIETIC CELL PROLIFERATION 3/60 13/42 43/74 38/59
  • LUNG: INFILTRATION, CELLULAR, HISTIOCYTIC 0/60 3/44 10/75 6/60
  • HEART: ATRIUM, THROMBUS 3/60 15/44 27/75 23/60
  • LIVER: DEGENERATION, CYSTIC 13/60 23/45 34/74 28/60; DEGENERATION, CENTRILOBULAR, DIFFUSE 0/60 4/45 9/74 10/60; NECROSIS, CENTRILOBULAR 4/60 13/45 10/74 6/60
Female Rats: Clear Evidence
Type Organ/Tissue (Lesion)
Neoplastic Lesions
  • Zymbal Gland: ADENOMA 0/60 3/45 4/75 3/60 OR CARCINOMA 1/60 10/45 17/75 13/60 COMBINED 1/60 12/45 21/75 16/60
  • Clitoral Gland: ADENOMA 5/58 15/44 13/74 16/55; CARCINOMA 2/58 17/44 41/74 30/55
  • Mammary Gland: ADENOCARCINOMA 1/60 2/45 14/75 20/60
  • Skin: SQUAMOUS CELL PAPILLOMA 0/60 0/45 3/75 0/60; BASAL CELL NEOPLASMS 0/60 4/45 3/75 2/60
  • Oral Cavity: SQUAMOUS CELL PAPILLOMA 2/60 2/45 3/75 3/60 OR SQUAMOUS CELL CARCINOMA 0/60 0/45 3/75 2/60 COMBINED 2/60 2/45 6/75 5/60
  • Large Intestines: ADENOMATOUS POLYP 0/60 0/45 1/75 2/60 OR ADENOCARCINOMA 0/60 1/45 0/75 1/60 COMBINED 0/60 1/45 1/75 3/60
  • Liver: NEOPLASTIC NODULE 0/60 1/44 0/75 2/60 OR CARCINOMA 0/60 0/44 0/75 1/60 COMBINED 0/60 1/44 0/75 3/60
  • Uterus/Cervix: ADENOMA 0/60 3/45 1/75 2/59 OR CARCINOMA 0/60 1/45 1/75 0/59 COMBINED 0/60 4/45 2/75 2/59
Non-Neoplastic Lesions
  • LUNG: INFILTRATION, CELLULAR, HISTIOCYTIC 0/60 3/45 4/75 18/60
  • LIVER: DEGENERATION, CYSTIC 1/60 2/44 1/75 5/60; DEGENERATION, CENTRILOBULAR 1/60 3/44 8/75 5/60; NECROSIS CENTRILOBULAR 1/60 2/44 6/75 5/60
  • SPLEEN: HEMATOPOIETIC CELL PROLIFERATION 3/60 22/44 50/75 47/60